Cord clamp for electrical devices



April 28, 1953 J. F. HEALY CORD CLAMP FOR ELECTRICAL DEVICES Ffiled June9. 1949 attornegs Patented Apr. 28, 1953 UNITED 601i!) J QLR E IQALREVWE-fi Joseph F. Heal-y, "Westport, Gonn, ,assignor to Harve Hub c l,c porated firidse crt, dean-5 a .ccre aii e of onnecti u ApplicationJune 9, 1949, Serial No. 98,040

9 maime- 1 This invention relates to electrical devices which areconnected to flexible electric cords or cables such as are used inoperating portable electrical devices and thelike, 5 and has for anobject to provide an improved clamping structure for securing the deviceto the cord or cable so as to take the strain of any pull on the cordand to greatly reduce or entirelyeliminate strain at the binding postsand thereby prevent the cord leads from breaking loose at point ofbinding post connection, and particularly to such a cord clamp or gripwhich maybe set bypressingoopposite sides together by means of a pair ofpliers, and does not require the use of screws or similar fasteners.

M r pecifically, this invention relates to an mmyemsnt ever he t pe of dvice des b d in United-States atent 1,679 23, issu d Au s .1928, to Havey Hubheh (L ui :E- Hu b lL Bis uit-ix In the device described i sa datent h dc ins po tion erates b 01 t ghtenin a pa cf sc ews to c s-amasi- 9f clamp n leme ts- ?Fl s patente d ic recla ms th threading ofscrew holes and also consumes the tim an e o o he el t ci n whe dam ithe cord t th dev ce- In t e de i e de c ibe and claimed in this. a licon, sc w inlet and screws a e ent e y elimin ted- Tm- 5: 1 can be e n tht hisz a cntionpro des-substantial saw inc .1" tim ef o and cost bo hthe manu ac ture a d us of th vice- W h the sc ee in n ther sw e i Viewhave c v ed e wn t ust il ust in t ac mpany ng drawing forming a part ofthis specification. It is however, to be understood the invention is notlimited to the specific details of construction and arrangement shown,but may embed-y various changes and modifications witht ei cq e f e i enn.

In t s dr wi Fig. l is a top plan view partly in section showts my nve oas applied o a s ca p t beingYbrokenaway to more clearly show theconstruction;

Fig. 2 isa side elevation thereof partly section;

We 3 is a t p p an iew of the clamp me ber removed;

Fig. 4 is a side elevation thereof Fig. 5 is a side view lookingsubstantially as indicated by line oi-.75 of Fig. 3;

Fig. -6 is a top plan view of anotherembodiment of my inventionin-openor loose position; and

Fig. 7 is a partial top plan of the embodiment shown in Fig. .6 inclosed .or clamped position.

(Cl. 173=e322l Although I have shown my improvedclamp as applied to aplug cap it will, of course, be understood that it is not limited tothis use, but may be employed with other electrical devices which areconnected to a conducting cable or cord in substantially the samemanner.

In the construction shown at Figs. 1 and 2, a circular insulating memberi4 is provided with a hole through its center to receive an electricalcord l8, carrying on the under side thereoi blade contacts ll connectedwithbinding posts having binding screws 9 for connection of lead wires18c from electrical cord E8 in the usual manner, and on the top side ofsaid insulating member oppoe site the blade and binding post side isprovided a pair ofaligned recesses it to receive the feet it of theclamping ears 2!]. A pair .of clamping elements shown at Figs. 3 and 4comprise a pair of mutually engaging members, each having a clamping.ear 2?} curved inwardly or concave to receive anelectrical cord andflared outwardly at the top, as shown at l9, to prevent cutting of thecord by sharp edges. An integrally connected pair of fingers extendslaterally, one from each edge of each of said clamping ears, one .of thepair of fingers ill being longer than the other finger l l. The longerfinger i0 is bent inwardly toward the clamping device and is termed withan inwardly curved hock 24. it is also bent at an angle at anintermediate point llla. An aperture i3 is provided in the side ofextended finger ill at a position on the are formed by the-hook 2.4 atthe end of said finger iii. 'Theshorter finger i l integrally connectedwith and extending later: ally from the opposite ed e of the clampingcar 28 is bent outwardly also to form a hook 125. The finger ll may beprovided with a lug 12 at its free end of less width than the finger andabout the same :length as opening it. Each clamping ear member till-isintegrally connected with a foot member :16 extendin outwardly from thecurve and at right angles to the clamping- {Surfaces of the ears 2.0.

In assembling the pair of clamping elements, the inward curves of theears 12 0 are placed opposite each other with end lug I32 of shortfinger ll of one clamping ear extending into aperture 1:3 of the longfinger w of the opp it clamping car.

There are provided a gripping surface 2.6 and 215a for pliers .or othertools on the exterior of the fingers it and H, and this may be knurled,serrated, corrugated or otherwise roughened to give a good grip topliers and other tools to prevent slippingef such tools.

The'ieet it of the clamping elements are re.-

tained in recesses l5 of the insulating member M by a metal shell orcasing I! which in the present construction encloses the body member M.It will be apparent from Fig. 2 that the feet I6 are located between theend wall of the shell Or casing 11 and the bottom of the recesses I5 inthe top of the insulating member [4, and are therefore held againstseparation from the insulating member M by this shell or casing, but areallowed to move toward and from the cable in tightening and looseningthe clamping elements. A convenient means of securing the shell casingto the body member is to bend its free end 21 over the opposite end ofthe body member M, as shown in Fig. 2. This shell also provides aprotective armor for the insulating member to protect it against injury.

In operation, the gripper edges 26 and 28a of opposing fingers Ill and Hare compressed together by pliers or other tools and the fingers bentand tightly formed, thereby securely and rigidly clamping the cord, asin Fig. 1. In this operation the finger l0 bends outwardly about thebend I01) and folds inwardly about the fold Na, and the hooked end offinger II is folded inwardly about the free end of finger H), the partsbeing thus folded to about the position shown in Fig. 1. It is,therefore, clear that an electrician can clamp the cord or cablesecurely with a pair of pliers in a fraction of the time required by thescrew method used in the patented device. Once the fingers are bent toclamping position the clamp holds the cord or cable rigidly securewithout the danger of clamping screws becoming loose or disengaged. Theclamping device thus described takes the strain of a pull on the cord,relieving strain at the binding posts.

In Fig. 6 I show another embodiment of the same invention in which theclamping ears 20a are formed with an outwardly bent hook 2| integrallyconnected and extending from each end of said ears. The hooks 2| engageinwardly curved hooks 23 of a pair of substantially U- shaped linkmembers 22 by extending their extremities through an aperture 28provided at each end of the U-shaped link member 22. The curved ends 23of member 22 are provided with apertures 29 corresponding to aperturesl3 of the first form, and the free ends of hooks 2| are provided withlugs 30 (corresponding to lugs 12 of the first form) to seat in theopenings 29 to prevent the elements from separating. The embodiment inFig. 6 is provided with integrally connected-feet l6, tool grippingsurfaces 26, inwardly or concavely curved clamping ears 2% formed toreceive an electric cord or cable, the top of said ears being likewiseflared outwardly as at l9 from the cord receiving curve so as to preventcutting of the cord by sharp metallic edges, as provided for and shownin the first mentioned embodiment of this invention. The plug cap, Figs.1 and 2, or other electrical devices may be combined with and receiveand use either embodiment of the clamping device.

Although both embodiments provide for sliding feet to engage in slidingrecesses, other means for connecting the clamping feet to the insulatingmember may be used, or the feet may be rigidly connected to theinsulating portion and the ears allowed to bend slightly when thefingers are squeezed together. The feet need not necessarily be at rightangles to the clamping ears, but may be in direct extension thereof intothe cord receiving aperture of the insulating member and various meansof connection with the insulating member may be used and either slidingor rigid connecting means may be employed. The clamping ears 20 and 20aof both forms may be provided with means on their inner or concavesurfaces for increasing their grip on the cord, such, for example, asrounded raised portions or bumps 30. These may be formed by bumpinginwardly with a tool on the opposite or outer side to form thedepressions 3|.

In operation, the embodiment shown at Fi 6 is used similarly to theother form of clamp shown in Fig. 3, by simply gripping the roughenedtool gripping surfaces 26 of the U-shaped links between a pair of pliersor other tool, bending the U-shaped link members 22 to bring hooks 2|closer together, thus rigidly clamping the cord or cable containedbetween the clamp ears 20. Fig. 7 illustrates the shape of the elementsin bent and closed position. The lugs l2 and openings [3 may or may notbe used with the form of device shown in Figs. 1 to 5, but should beused with the form of Figs. 6 and 7 to secure the links 22 to theclamping members 22a.

Having thus set forth the nature of my invention, I claim:

1. An electric cord clamping device for use in combination with electricdevices comprising a pair of clamping ears curved inwardly to receiveand grip an electric cord, an integrally formed hook at each end of eachclamping ear, angularly shaped linking means for engaging the hooks atthe opposite sides of the ears and squeezing toward each other the hooksof one clamping ear with the opposing hooks of the opposite clamping earwhereby an electrical cord placed through the pair of clamping ears maybe rigidly clamped between said ears and held in rigid, connection bythe tight compression and engagement of the opposing hooks with thelinking means, and means for connecting the clamping ears to anelectrical device so that an electric cord may be attached to thebinding posts of said electric device and prevent pull on the cord fromstraining the binding post connections.

2. An electrical cord clamping device for use with an electrical devicecomprising an insulating member provided with an electrical cordreceiving aperture, and a pair of binding posts, said cord clampingdevice comprising a pair of inwardly curved clamping ears, a pair offingers laterally connected with each clamping ear, means for connectingthe pair of clamping ears with the insulating member, whereby anelectric cord connected with the binding posts may be extended throughthe cord receiving aperture of the insulating member and between theclamping ears, said clamping ears being connected by opposing pairs or"fingers having inclined curved portions extending one within the otherand the outer surfaces of an opposed pair of fingers having spacedsurfaces which may be clamped between the jaws of a pair of pliers orsimilar tool to force the fingers of a pair together and interlock themtogether to draw the ears toward each other and clamp them on oppositesides of the cord.

3. A cord clamping member for electrical devices comprising a pair ofinwardly curved clamping ears at each end of which is formed a shortoutwardly curved hook, a sliding foot member connected with eachclamping ear and extending outwardly at right angles to the plane of theelectric cord passage between said clamping ears, a pair of U-shapedlinks formed with a small inwardly curved hook and an aperture in eachside at each extremity, means for holding the feet of said cord clampingmember against separation from the electrical device with sufiicientfreedom to permit said clamping ears to move toward and from a cordbetween them, the outwardly curved hooks of the clamping ears extendedthrough the ape tures in the sides at the extremities of the Um nedlinks, said U-links having spaced outer su ces to engage between a pairof jaws whereby the of said links may be squeezed and compressedtogether with a pair of pliers or similar tool so as to draw theclamping ears tightly together and clamp the electric cord in rigidposition.

4. In a device of the character described, a conductor cord clamp forelectrical devices comprising a pair of cord clamping elements havingclamping ears formed with outwardly curved hooks, a pair of removablelinks of suitable size and comprising an ularly arranged side portionsprovided. with inwardly curved end portions removably engaging theoutwardly curved hooks of the clamping ears, and feet extending at anangle to clamping portion adapted to be slidably connected with theelectrical device and the outer surfaces of curved end portions providinspaced. surfa es which may be clamped between a pair or" pressure jawsto force said curved end portions toward each other to interlock withthe hooks on said ears and draw the ears toward each other to clamp theears on the cord.

5. In a cord clamp for an electrical device having binding posts forattaching to lead wires of an electric cord, a clamping element of thecharacter described comprising a pair of cord clamping ears, said earsformed at each edge with an outwardly curved hook, a pair ofsubstantially U- shaped connecting links provided with an aperture ateach free end, means for mounting said clamping element on tie device,the outer sur faces of the end portions of a link providing spacedclamping surfaces to be gripped between the jaws of a pair of pli rs orthe like to force said end portions and connected hooks towarc eachother to clamp and retain the ears on the cord.

6. A cord clamp for securing electric conductor cords with its leadconnected to securing means of an electric device, said clamp comprisinga pair of clamping ears curved inwardly to receive and grip the cord, apair of laterally extending opposed gers integral with and extendinglaterally from he clamping ears, one of said fingers beir longer thanthe other and comprisitially straight portion adjacent the and extendingoutwardly therefrom, a second po tion connected to the outer end andinclined outwardly and laterally to the first portion. toward theopposed finger, and a third pertion at the outer end of the secondportion and inclined inwardly and provided with an inwardly andbackwardly curved end portion provided with an opening, the shorterfinger comprising a substantially straight outwardly extending portionadjacent its attached ear and a laterally and inwardly bent end portionat the inner side of the curved portion of the first finger and providedwith a lug in the opening of the other finger, said first substantiallystraight portion of the first finger and the outer portion of its curvedend forming spaced gripping surfaces which may be clamped between a pairof jaws and pressed toward each other to bend and lock the fingertogether and clamp the ears about the cord.

7. A clamp for a cord containing conductor wires leading to anelectrical device, comprising a pair of curved ears to clamp oppositesides of the cord, a pair of opposed fingers extending outwardly fromthe opposite edges of the ears, one pair of fingers comprising a longerfinger including a substantially straight portion extending outwardlyfrom its connected ear and an inclined portion at its outer end inclinedtoward the other car and including an inwardly and backwardly curved endportion provided with an opening, the longer finger comprising asubstantially straight portion extending outwardly from its connectedear and a laterally and inwardly inclined portion within the curved endportion of the other finger and provided with a lug in the opening inthe other finger, and the outer surfaces of said strai ht and curvedportions of the first finger providing spaced clamping surfaces whichmay be clamped between a pair of pressure jaws to force said surfacestoward each other and fold the end portions of the two fingers togetherto clamp and lock the ears on the cord.

8. In a cord clamp for electrical devices, a pair of clamping elementscomprising a pair of opposing clamping ears and movable toward eachother to clamp between them a conductor cord leading to an electricaldevice, said ears being each provided on its outer edges with alaterally and inwardly curved hook provided with an opening, and aconnecting link for the pair of hooks at each side of the clampcomprising a member including angularly arranged side portions eachprovided with a curved end portion to interlock with one of the hooksand provided with a lug seated in the opening in this hook, and theouter surfaces of the curved end portions of the link providing spacedclamping surfaces to be clamped between a pair of pressure jaws to forcesaid curved end portions and interlocked hooks toward each other toclamp the ears on the cord.

9. A cord clamp for electrical devices comprising a pair of ears to belocated and clamped on opposite sides of a conductor cord connected tothe device, and clamping means for clamping said ears on the cordcomprising an outwardly and laterally extending member on a side edge ofone ear forming a hook at its outer portion, an angularly shapedconnecting member connected with the other car and provided with acurved end portion interlocked with the hook, and the outer surfaces ofthe connecting member providing a pair of spaced clamping surfaces to beengaged and clamped between a pair of pressure jaws to force theopposite sides of said angularly shaped member toward each other to drawthe jaws laterally and clamp them about the cord.

JOSEPH F. HEALY.

References Cited in the file of this patent UNITED STATES PATENTS Number

